FG datum for earthwork

[jmayo-EE]

I have a commercial site with a bunch of blds, parking areas and access aisles. We have a composite FG surface and I need to create a datum srf for the pavement depth and the underground stormwater storage below the pavement.

How would you go about this? I have tried to paste FG into an empty surface, lower it to pavement depth, apply boundaries as required. The surface looks good but it won't paste into the FG. I'm figuring this is because there is no common tie between the srf's. As I attempt to get this tie in created I was wondering if you folks had some other thoughts on this process besides a full blown corridor (pilot project in the works).

[jmayo-EE]

Yes I think that is the way to handle it Troma. Thx.

[MikeEvansUK]

John, I think it is a necessary step when dealing with curves as you want more nodes around the curves so the triangulation is correct.

You can use 2d polylines but need "segmented curves" it seems easiest to elevate the polylines then convert to 3d for use.

I am surprised with this method, I just missed it completely and regret it now. I am currently looking at the difference it generates and potential problems so I can use this in the future.

[jmayo-EE]

I tell you Mike I do like this method. It is quick and easy but it also makes a large file without FLines. My earthwork file is 145MB with only DRefs, plines and the required subgrade surfaces to build. When I used copies of the FG surface with boundaries and lowered the diff subgrade areas the file was only 35MB.

I think my original issue of the lowered surfaces not pasting together is because I am using hidden boundaries to remove unwanted surface areas. I need to check and confirm this though.

[Joe-Bouza]

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@jmayo wrote:

I have a commercial site with a bunch of blds, parking areas and access aisles. We have a composite FG surface and I need to create a datum srf for the pavement depth and the underground stormwater storage below the pavement.

How would you go about this? I have tried to paste FG into an empty surface, lower it to pavement depth, apply boundaries as required. The surface looks good but it won't paste into the FG. I'm figuring this is because there is no common tie between the srf's. As I attempt to get this tie in created I was wondering if you folks had some other thoughts on this process besides a full blown corridor (pilot project in the works).

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If thats not a typo, then there is you reason.

[jmayo-EE]

Hey Joe. I did get one surface to paste correctly once I had the tie-ins but I still had issues with two other surfaces. I will hopefully have time to test this and report back but as I said above these two surfaces have hidden boundaries. The other did not.